Expandable painting wagon having a rack and pinion drive mechanism

ABSTRACT

A paint wagon ( 10 ) has a base ( 22 ) having a plurality of wheels ( 28, 30 ) mounted in supporting relation thereto. A drop pin ( 32 ) is slidably mounted to the base. The drop pin ( 32 ) selectively engages with a conveyor ( 12 ) for translating the paint wagon ( 10 ) along a path. A plurality of slidably mounted mounting fixtures ( 26 ) are movable between a contracted position and an expanded position. An actuating assembly ( 24 ) slidably mounts the mounting fixtures to the base. The actuating assembly ( 24 ) has a longitudinal support ( 38 ) and a plurality of cars ( 52, 54, 56 ) in sliding engagement with the longitudinal support. The mounting fixtures ( 26 ) extend from the plurality of cars. A rotatably mounted pinion ( 70 ) drivingly engages a rack ( 84, 86 ) which is slidably mounted with the longitudinal support. The rack ( 84, 86 ) is connected to an outer car ( 56 ). The rack has a plurality of tabs ( 90, 92 ) extending therefrom positioned to selectively engage inner cars ( 52, 54 ) to move the inner cars and automatically space the cars. An actuating mechanism ( 20 ) is mounted on the path. The actuating assembly ( 24 ) selectively engages the actuating mechanism ( 20 ) as the paint wagon ( 10 ) travels along the path to effect rotation of the pinion ( 70 ) and responsively effect the movement of the mounting fixtures ( 26 ) between the contracted and expanded positions.

This application claims the benefit of Provisional application No.60/210,881 filed Jun. 9, 2000.

FIELD OF THE INVENTION

The present invention relates to a paint wagon for carrying a pluralityof components to be painted through a painting facility. In particular,this invention relates to an expandable paint wagon which can be easilyexpanded and contracted at desired locations.

BACKGROUND OF THE INVENTION

Paint wagons are commonly used to carry exterior components of motorvehicles through a paint facility. U.S. Pat. No. 5,772,233 describes atypical paint wagon used for two tone fascias. The paint wagon contractsprior to entry into the paint facility so that one fascia will partiallyshroud a next adjacent fascia. After painting, the wagon expands toallow removal of the fascia from the wagon.

More commonly, paint wagons are not expandable and have mountingfixtures which are rigidly mounted to the wagon. These wagons are usedprimarily because they are easy to build and have no moving parts whichcan foul with each trip through the paint facility. However, fixed mountpaint wagons limit the throughput of the paint facility since each wagonrequires a minimum of space along the conveyor to allow the wagons torun corners. In many cases, the fascia must be spaced apart to allow thepainting robot to fit between the parts and to allow the mounting andremoval of the fascia onto and from the paint wagon. At other times, thenon-expandable wagons take up valuable space along the conveyor system.

The expandable wagon as described in U.S. Pat. No. 5,772,233 couldeasily be modified to expand prior to entry into the paint facility andcontract after and at other desired locations. However, the prior artexpandable wagons require contact with a fixed rigid structure to expandand contract. Usually, a pole is mounted on the floor adjacent thetravel of the paint wagons to effect the movement of the paint wagon.Although a number of poles could be installed about the conveyor, thesepoles would present safety problems. Further, the greater number ofpoles may interfere with other fixtures mounted on the paint wagons.Other fixtures are utilized when parts other than fascia are required tobe painted. Thus, the addition of poles is not a safe and economicalsolution to modifying paint wagon length.

SUMMARY OF THE INVENTION

The disadvantages of the prior art may be overcome by providing anexpandable paint wagon having a simple actuating mechanism which can betriggered by a low profile mechanism.

According to one aspect of the invention, there is provided a paintwagon which has a base having a plurality of wheels mounted insupporting relation thereto. A drop pin is slidably mounted to the base.The drop pin selectively engages with a conveyor for translating thepaint wagon along a path. A plurality of slidably mounted mountingfixtures is movable between a contracted position and an expandedposition. An actuating assembly slidably mounts the mounting fixtures tothe base. The actuating assembly has a longitudinal support and aplurality of cars in sliding engagement with the longitudinal support.The mounting fixtures extend from the plurality of cars. A rotatablymounted pinion drivingly engages a rack which is slidably mounted withthe longitudinal support. The rack is connected to an outer car. Therack has a plurality of tabs extending therefrom positioned toselectively engage inner cars to move the inner cars and automaticallyspace the cars. An actuating mechanism is mounted on the path. Theactuating assembly selectively engages the actuating mechanism as thepaint wagon travels along the path to effect rotation of the pinion andresponsively effect the movement of the mounting fixtures between thecontracted and expanded positions.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred embodiment of the invention will now be described, by way ofexample only, with reference to the attached Figures, in which:

FIG. 1 is a perspective view of a paint wagon with actuating mechanismof the present invention;

FIG. 2 is a perspective view of the paint wagon and actuating mechanismof FIG. 1;

FIG. 3 is a partial sectional view of the actuating assembly of thepaint wagon of FIG. 1;

FIG. 4 is a partial perspective view of the actuating assembly of thepaint wagon of FIG. 1;

FIG. 5 is a partial perspective view of the actuating assembly of thepaint wagon of FIG. 1;

FIG. 6 is a partial perspective view of the locking mechanism of theactuating assembly of the paint wagon of FIG. 1;

FIG. 7 is a perspective view of the actuating mechanism of the paintwagon of FIG. 1;

FIG. 8 is a top plan view of the actuating mechanism of FIG. 7 in anengaged position;

FIG. 9 is a top plan view of the actuating mechanism of FIG. 7 in adisengaged position;

FIG. 10 is a side schematic view of the actuating assembly of the paintwagon of FIG. 1, moving to an expanded position; and

FIG. 11 is a side schematic view of the actuating assembly of the paintwagon of FIG. 1, moving to a contracted position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to FIG. 1, an expandable paint wagon 10 of the presentinvention is shown. The paint wagon 10 travels along a conveyor 12 inthe direction indicated at 14. The conveyor 12 is conventionally mountedbelow floor 16 and accessed through a slot 18.

An actuating mechanism 20 is mounted on the floor 16 adjacent to theslot 18. Actuating mechanism 20 is generally elongate and extends in thesame general direction as the slot 18.

Referring to FIG. 2, the paint wagon 10 is illustrated in greaterdetail. The paint wagon 10 generally comprises a base frame 22, anactuating assembly 24 and a fixture mounting assembly 26. Actuatingassembly 24 is mounted on the base frame 22. Fixture mounting assembly26 is operably mounted on the actuating assembly 24 for responsivemovement between an expanded condition (FIG. 2) and a contractedcondition (FIG. 1).

Base frame 22 is preferably an H-shaped frame having wheel assemblies28, 30 suitably mounted at each of the four legs of the H-shaped frameto support the paint wagon 10. Preferably wheel assemblies 28 are casterwheels which allows the paint wagon 10 to be guided along and steered.

A drop pin 32 is slidably mounted at the front of the frame 22. The droppin 32 extends downwardly to engage a socket 34 on the conveyor chain12. When engaged with the conveyor chain 12, the drop pin 32 provides adriving engagement to the paint wagon 10 to translate the paint wagon 10along floor 16. The drop pin 32 is lifted to disengage the paint wagon10 from the conveyor chain 12.

Referring to FIGS. 3 and 4, the actuating assembly 24 comprises anelongated C-shaped longitudinal support 38 having closed ends 40.Longitudinal support 38 is mounted on spacers 36. An elongate channel 42extends longitudinally along one side of the longitudinal support 38.The upper edge 44 and the lower edge 46 of the channel 42 define guides.A fixed plate 48 is welded to the longitudinal support 38 across theopen channel 42. Stationary mounting arm 50 extends from plate 48.

Inner cars 52, middle cars 54 and end cars 56 are mounted on the upperand lower guides 44, 46 for sliding movement outwardly and inwardlyrelative to fixed plate 48.

Actuating assembly 24 is symmetrical about a diagonal across plate 48and therefore only one side will be described in detail.

Each of the cars 52, 54, 56 has a mounting plate 58 on which rollers 60are rotatably mounted. Preferably, four rollers 60 are spaced about oneface of mounting plate 58 so that the rollers engage guides 44, 46. Therollers 60 mount the cars 52, 54, 56 for guided travel along theactuating assembly. A mounting arm 62 extends outwardly from themounting plate 58. Cars 52, 54, 56 are identical except that inner cars52 have a tab 64 projecting from the leading edge when the cars aremoving in an expanding direction and middle cars 54 have a tab 66projecting from trailing edge when the cars are moving in an expandingdirection. Middle cars 54 and outer cars 56 each has a spacer bar 68extending from the leading edge when the cars are moving in acontracting direction.

Actuating assembly 24 further comprises a pinion 70 mounting on a driveshaft 72. Bevel gear 74 is also mounted on the drive shaft 72 on an endopposite pinion 70. Bevel gear 74 drivingly engages a matching bevelgear 76 which is mounted on a vertically extending shaft 78. Bearings80, 82 are provided to journal mount shafts 72, 78, respectively.

Racks 84, 86 are slidably mounted within longitudinal support 38. Thedistal end of each rack 84, 86 is affixed to the outer cars 56. Racks84, 86 each has a set of teeth 88 along a near end thereof for engagingwith pinion 70. Racks 84, 86 extend in opposite directions on oppositesides of the pinion 70. Rotation of pinion 70 in a first sense will moveboth racks 84, 86 outwardly in an expanding direction and rotation inthe opposite sense will move both racks 84, 86 inwardly in a contractingdirection.

Racks 84, 86 each has an inner tab 90 and a middle tab 92 (See FIGS. 10,11). Middle tab 92 extends is a direction orthogonal from inner tab 90.Tabs 90, 92 are spaced at a distance to provide a desired separationbetween parts to be painted. Inner tab 90 will contact tab 64 on innercars 52 when the racks 84, 86 are moving in the expanding direction andurge the inner cars 52 in the expanding direction. Middle tab 92 willcontact tab 66 on middle cars 54 when the racks 84, 86 are moving in theexpanding direction and urge the middle cars 54 in the expandingdirection. Middle tab 92 and inner tab 90 are orthogonal so that theracks 84, 86 will only engage the middle cars 56 and the inner cars 52,respectively, during expanding movement and not during contractingmovement.

Referring to FIGS. 5 and 6, the lower end of shaft 78 has a spur gear94. Mounted in front of and parallel to shaft 78 is a lock shaft 96.Lock shaft 96 has a floor engaging roller 98 at the lower end and asection of a bevel gear 100 at the upper end. A spring 102 mountsbetween the housing 104 and the lock shaft 96 to bias the lock shaft tothe down or lock position. Lock shaft 96 has a key 106 which preventrotation of the lock shaft and limits movement to the verticaldirection. In the lock position, bevel gear 100 engages bevel gear 76 toprevent rotation thereof.

Referring to FIG. 7, the floor mounted actuating mechanism 20 isillustrated in greater detail. The cover 108 has been removed to showthe inner detail. Bar 110 is pivotally mounted on cover 18 near theleading edge thereof. Bar 110 has a ramp 109 and an elevated surface 107for receiving roller 98 of lock shaft 96 and urging the lock shaft 96upwardly to the raised position and to unlock the actuating assembly 24.Bar 110 has a spring 111 extending between the trailing end and thecover 108. A shock absorber 113 also extends from the trailing end andthe cover 108. The spring 111 and shock absorber 113 control the pivotalmovement of the bar 110.

A sleeve 112 is slidably mounted on bar 110 for travel in the directionof travel 14. A spring 114 extends between the sleeve 112 and bar 110and urges the sleeve towards the leading edge of the cover 108. A shockabsorber 116 is pivotally mounted at one end to the sleeve 112 andpivotally mounted at the opposite end to the cover 108. Sleeve 114 hasan abutment 118 at the trailing end thereof. Sleeve 112 has an L-shapedflange 120 having a rack of teeth 122 which are complementary to andoperatively engage the bevel gear 94. The leading edge of the rack ofteeth 122 is slightly tapered to allow smooth engagement between theteeth 122 and bevel gear 94.

Cover 108 has a stop 124 positioned near the trailing end of the cover108. Bar 110 will rest against the stop 124 under the influence ofspring 111. Stop 124 will also engage abutment 118 of sleeve 112 as thesleeve 112 is moved towards the trailing end which will cause the sleeve112 and the rack of teeth 122 to pivot outwardly to disengage the rackof teeth 122 from the bevel gear 94.

Cover 108 is firmly attached to the floor 16, adjacent the slot 18.Cover 108 is generally a C-shaped extrusion having an open channelfacing upwardly and extending in the direction of travel. The leadingedge of the slot is preferably tapered to receive lock shaft 96.

Referring back to FIG. 2, the fixture mounting assembly 26 comprises aplurality of U-shaped supports 126. Each of the supports 126 are mountedon one of the fixed arm 50 or movable arms 62. In the preferredembodiment, the paint wagon has seven mounting fixtures, six movablefixtures and one stationary fixture. It is apparent to those skilled inthe art that any number of fixtures could be accommodated.

Housing 104 shrouds the gear or operating components of the paint wagon10 from paint over spray. Preferably, cars 52, 54 and 56 are made fromstainless steel in order to minimize damage from the paint and therequisite cleaning solvents needed to clean and remove over sprayedpaint. The preferred shape of mounting arms 62 is as illustrated in FIG.2. The shape allows a further shroud to be placed over the channel 42further minimizing the risk of paint being applied to the cars 52, 54and 56.

In operation, the paint wagon 10 of the present invention is selectivelyengaged to the conveyor 12. The paint wagon 10 will be pulled about inthe direction of travel 14. In this condition, the lock shaft 96 will bein the down or locked position, holding the fixture mounting assembly 26in place in the contracted condition. The paint wagon 10 will encounterone of a desired number of actuating mechanisms 20.

Referring to FIG. 5, the roller 98 will engage the ramp 109 which willlift the lock shaft 96 upwardly, disengaging the bevel gear 94 of theactuating assembly 24. As the paint wagon 10 travels along, spur gear 94will engage rack of teeth 122 which will cause rotation thereof in anexpanding sense. Rotation of spur gear 94 will in turn rotate pinion 70,which in turn will cause outwardly movement of the racks 84, 86.

Referring to FIGS. 10 and 11, the outward movement of the racks 84, 86will cause direct movement of the outer cars 56, since racks 84, 86 isdirectly connected to one of the outer cars 56. Inner tab 90 and middletab 92 will contact tabs 64 and 66, respectively, to move cars 52, 54 toeach respective expanded position.

Referring to FIGS. 7, 8 and 9, the disengagement of the actuatingmechanism 24 is illustrated. Once the paint wagon 10 has reached theexpanded position, the racks 84, 86 will stop moving. This will causepinion 70 to stop rotating and in turn stop spur gear 94 from rotating.If the spur gear 94 has not disengaged from the rack of teeth 122, thespur gear 94 will cause the rack of teeth 122 and sleeve 112 to slidealong the bar 110 until abutment 118 engages stop 124. Engagement of theabutment 118 with stop 124 will cause bar 110 and the sleeve 112 topivot outwardly to cause the rack of teeth 122 to disengage from thespur gear 94. Once the spur gear 94 has traveled beyond the rack ofteeth 122, the spring 111 will return the bar 110 and sleeve 112 back toa ready position in parallel to the direction of travel 14. Once thepaint wagon 10 has traveled beyond the bar 110, the lock shaft 96 willfall off the trailing edge of the bar 110 allowing the lock shaft tomove downwardly to the lowered position to re-engage the bevel gear 100with the bevel gear 76, locking the actuating assembly 24 in place.

To contract the paint wagon 10, an actuating mechanism 20 is mounted onthe floor 16. The contracting actuating mechanism 20 is a mirror imageof the mechanism shown in the FIGS. 7, 8, and 9. The rack of teeth 122will be on the opposite side of the bar 110 and will rotation of thespur gear 94 in a contracting sense opposite the expanding sense.

Rotation of the spur gear 94 in the contracting sense will causerotation of the pinion 70 in the contracting sense. Pinion 70 will causeracks 84, 86 to move inwardly. Racks 84, 86, will move the outer cars 56inwardly which will urge middle cars 54 inwardly and then inner cars 52inwardly to the contracted position. Bars 68 will space the outer cars56 from the middle cars 54 from the inner cars 52. By selecting thelength of bars 68, a minimum spacing between supports 126 is determined.

As is apparent, any number of actuating mechanisms 20 can be placedabout the length of the conveyor 12 to expand and contract the paintwagon 10 as desired. Preferably, the paint wagons 10 are contracted toturn corners and expanded for painting, mounting and dismounting partsto be painted onto and from the paint wagon 10. The actuating mechanisms20 have a low profile minimizing risk of contact by fork lift trucks andworkers. Additionally, actuating mechanisms 20 are mounted directlyunder the path of travel of the paint wagons 10 and therefore not in anarea normally accessed by workers.

While presently preferred embodiments of the present invention aredescribed herein, variations and modifications will occur to thoseskilled in the art and should not be considered as departing from thescope of the invention as defined by the appended claims. floor 16. Thecontracting actuating mechanism 20 is a mirror image of the mechanismshown in the FIGS. 7, 8, and 9. The rack of teeth 122 will be on theopposite side of the bar 110 and will rotation of the spur gear 94 in acontracting sense opposite the expanding sense.

Rotation of the spur gear 94 in the contracting sense will causerotation of the pinion 70 in the contracting sense. Pinion 70 will causeracks 84, 86 to move inwardly. Racks 84, 86, will move the outer cars 56inwardly which will urge middle cars 54 inwardly and then inner cars 52inwardly to the contracted position. Bars 68 will space the outer cars56 from the middle cars 54 from the inner cars 52. By selecting thelength of bars 68, a minimum spacing between supports 126 is determined.

As is apparent, any number of actuating mechanisms 20 can be placedabout the length of the conveyor 12 to expand and contract the paintwagon 10 as desired. Preferably, the paint wagons 10 are contracted toturn corners and expanded for painting, mounting and dismounting partsto be painted onto and from the paint wagon 10. The actuating mechanisms20 have a low profile minimizing risk of contact by fork lift trucks andworkers. Additionally, actuating mechanisms 20 are mounted directlyunder the path of travel of the paint wagons 10 and therefore not in anarea normally accessed by workers.

While presently preferred embodiments of the present invention aredescribed herein, variations and modifications will occur to thoseskilled in the art and should not be considered as departing from thescope of the invention as defined by the appended claims.

We claim:
 1. A paint wagon comprising: a base having a plurality ofwheels mounted in supporting relation thereto; a drop pin slidablymounted to said base, said drop pin selectively engagable with aconveyor for translating said paint wagon along a path; a plurality ofslidably mounted mounting fixtures, said fixtures movable between acontracted position and an expanded position, an actuating assemblyslidably mounting said mounting fixtures to said base, said actuatingassembly comprising: a longitudinal support mounted to said base, aplurality of cars in sliding engagement with said longitudinal support,said plurality of cars each having one of said mounting fixtureextending therefrom, a rotatably mounted pinion, a first rack slidablymounted with said longitudinal support, said pinion in drivingengagement with said first rack, said first rack connected to an outerone of said cars, said first rack having a plurality of tabs extendingtherefrom positioned to selectively engage inner ones of said cars tomove said inner ones outwardly and automatically space said cars,wherein rotation of said pinion effects said movement of said mountingfixtures between the contracted and expanded positions.
 2. A paint wagonas claimed in claim 1 wherein each of said cars has a bar positioned tospace said plurality of cars from an adjacent car upon moving saidmounting fixtures to said contracted position.
 3. A paint wagon asclaimed in claim 2 wherein said paint wagon further comprises a secondrack slidably mounted with said longitudinal support, said pinion indriving engagement with said second rack, said second rack connected toan outer one of said cars, said second rack having an plurality of tabsextending therefrom positioned to selectively engage inner ones of saidcars to move said inner ones outwardly and automatically space said carswhen moving to the expanded condition.
 4. A paint wagon as claimed inclaim 3 wherein said second racks extends in a direction opposite tosaid first rack.
 5. A paint wagon as claimed in claim 4 wherein saidpaint wagon has a fixed mounting fixture positioned between mountingfixtures operatively engaging said first rack and mounting fixturesoperatively engaging said second rack.
 6. A paint wagon as claimed inclaim 5 wherein said actuating assembly further comprises a downwardlyextending shaft having a gear mounted thereon, said shaft operativelyengaging said pinion, said gear positioned to engage a complementaryrack of teeth fixed relative to said paint wagon such that as said paintwagon translates along said path said gear rotates effecting rotation ofsaid pinion.
 7. A paint wagon as claimed in claim 6 wherein saidactuating assembly further comprises a lock shaft slidable mounted infront of said shaft, said shaft movable between a lowered position and araised position, said lock shaft engaging said shaft preventing rotationthereof when said lock shaft is in said lowered position and said lockshaft disengaging from said shaft when said lock shaft is in said raisedposition.
 8. A paint wagon as claimed in claim 7 wherein said paintwagon has a housing to shroud operative components of said paint wagonfrom paint spray.
 9. A paint wagon as claimed in claim 8 wherein saidlongitudinal support is a C-shaped section having an elongated openchannel defining upper and lower guides, and each of said cars has aplurality of rotatably mounted wheels engaging said upper and lowerguides.
 10. A paint wagon as claimed in claim 9 wherein said paint wagonhas at least three cars and said inner ones of said cars comprise aninner car and a middle car positioned between said outer one of saidcars and said inner car, said inner car having a tab on a leading edgewhen said inner car is moving in an expanding direction, said inner cartab engaging one of said plurality of tabs on a respective rack and saidmiddle car having a tab on a trailing edge when said middle car ismoving in an expanding direction, said middle car tab engaging anotherof said plurality of tab on a respective rack.
 11. A paint wagon asclaimed in claim 10 wherein said plurality of tabs on said rack projectorthogonally therefrom.
 12. A paint wagon as claimed in any precedingclaim, in combination with an actuating mechanism mounted along saidpath, said actuating assembly selectively engaging said actuatingmechanism as said paint wagon travels along said path responsivelyeffecting rotation of said pinion and to effect said movement of saidmounting fixtures between the contracted and expanded positions.
 13. Acombination as claimed in claim 12 wherein said actuating mechanismcomprises: a housing having an upwardly extending slot for receivingsaid drop pin as said paint wagon travels past said actuating mechanism,a pivotally mounting bar presenting a ramp and an elevated surfaceeffecting movement of said lock shaft between said lowered and raisedpositions, a stop, and said rack of teeth slidably mounted to cooperatewith said bar, said rack of teeth biased to a leading edge of saidactuating mechanism, said bar biased to urge said rack of teeth intoengagement with said gear, said rack of teeth slideable relative to saidbar when said gear stops rotating until said rack of teeth engages saidstop whereupon said stop pivots said rack of teeth out of engagementwith said gear.
 14. A combination as claimed in claim 13 furthercomprising a series of actuating members positioned along said path foralternately effecting movement of said mounting fixtures between saidcontracted and expanded positions.